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The Earth in Space
TEK 8.7C Relate the position of the Moon and Sun to their effect on ocean tides
But first –
let’s review!
Name this phase!
Full Moon
Name this phase!
First Quarter
Name this phase!
Waxing Crescent
Name this
phase!
Waning
Gibbous
Name
this
phase!
Third Quarter
Name this phase!
Waxing Gibbous
Name this phase!
Waning Crescent
Name this phase!
Full Moon
Name this phase!
New Moon
Name this phase!
Waning Gibbous
Name this
phase!
Waning Crescent
Mr. Lee – Moon Phase Rap
Ocean Tides
Lunar Eclipses
Eclipses
The Sun and Moon occasionally
line up causing an eclipse
Two types of Eclipses:
Solar Eclipse
Lunar Eclipse
Eclipses are named for which
object is blocked from our view on
Earth
Moon moves between the Earth and Sun
The Moon’s shadow covers part of the Earth
Only happens during a New Moon
Total eclipses are rare occurrences
Total Solar Eclipse
Only lasts a few
minutes
Path of Totality
about 10,000 miles
long, only 100 miles
wide
Observers in the “umbra” shadow see a total eclipse (safe to
view the Sun)
Those in “penumbra” see a partial eclipse (NOT safe to look
directly at Sun)
Words to Know
Umbra – the darkest part of the shadow
during an eclipse (people in the umbra will
see a total eclipse)
Words to Know
Penumbra - the lighter part of the shadow
during an eclipse (people in the penumbra
will see a partial eclipse)
Photo of a Total Eclipse
Partial Solar Eclipse
• Earth moves between the Sun and the Moon
• Moon is in Earth’s shadow – this shadow darkens
the moon
• Can only occur at a Full Moon
• About 2-3 lunar eclipses per year
• Last up to 4 hours
Lunar Eclipse
Checkpoint
Why do lunar eclipses occur only during a
Full Moon? Where are the Earth, the Sun,
and the Moon located in relation to each
other during a lunar eclipse?
Answer: Earth must come between the
sun and the moon during a lunar eclipse;
this only happens during the full moon
phase.
Tides
Tides Animation
The rise and fall of water,
every 12.5 hours
The water rises for about
6 hours, then falls for
about six hours, in a
regular cycle
Two high tides and two
low tides every day
The Tides
Tides are caused by the pull of Moon’s gravity on
Earth
We have both low tides and high tides
High tide: occurs in areas where side is
facing Moon and the side away from Moon
Also called Spring Tides
Low tide: occurs on sides of Earth
Also called Neap Tides
The Moon’s Gravity
The Moon’s gravity tugs on the Earth
Tides occur mainly because of
differences in how much the moon
pulls on different parts of the Earth
It pulls the most on the part of
Earth closest, which raises the
atmosphere, the oceans, and even
the rocks (a little)
It pulls the least on the part of
Earth that’s farthest away
Moon’s gravitational pull
High Tides and the Tide Cycle
As Earth rotates, one high
tide stays on the side of
Earth facing the moon
The second high tide stays
on the opposite side of
Earth
Every location on Earth
sweeps through those two
high tides and two low tides
in a 25-hour cycle
Tides and the Lunar Cycle
During New and Full Moon
- Spring Tides
greatest difference
between high and low
tide
During First and Last
Quarter - Neap Tides
least difference
between high and low
tide
Spring Tide or High Tide
The gravity of the sun and the
moon pull in the same direction
The combined forces produce
a tide with the greatest
difference between low and
high tide
Spring Tides occur twice a
month
The sun’s gravity also pulls on Earth’s waters
During a New and Full moon - the Sun, Earth, and moon are
nearly in a line (parallel)
Neap Tides or Low Tides
The sun’s pull is at right angles
to the moon’s
This arrangement produces a
tide with the least difference
between low and high tide
During First and Last Quarter moons - the line between
the Sun, Earth, and moon is a right angle
Tidal Forces on
Earth
January 24, 2011
Bay of Fundy Observations
Bay of Fundy Video
Bay of Fundy
Ocean Tides at the Bay of Fundy
January 24, 2011
Bay of Fundy Observations
Local Tide Effects
The shapes of bays, inlets, and the ocean
floor can affect the flow of water, so that
the height and timing of the tides can vary
even in places that are close to each other
The positions of the moon,
Earth, and the Sun cause the
phases of the moon, eclipses,
and tides
Worksheet